Johnson & Johnson is accelerating work on its experimental Ebola vaccine and said on Wednesday that it aims to have 1 million doses ready in 2015, of which 250,000 are expected to be available by May.
There is currently no proven vaccine against the deadly disease but several companies are racing to develop products and clinical tests on two - from GlaxoSmithKline and NewLink Genetics - are already under way.
The World Health Organization hopes that tens of thousands of people in West Africa, including frontline healthcare workers at high risk of infection, can start receiving Ebola vaccines from January as part of large-scale clinical trials.
J&J said it would test its vaccine for safety and immune response in healthy volunteers in Europe, the United States and Africa from early January, adding that it will commit up to $200 million to accelerate the programme.
The J&J vaccine was discovered in collaboration with the U.S. National Institutes of Health (NIH) and includes technology from Denmark-based Bavarian Nordic, which will now receive a cash injection from the U.S. healthcare group.
Bavarian will receive an upfront payment of $25 million and up to $20 million in milestone payments based on future success of the product. J&J will also invest 251 million Danish crowns ($43 million) in Bavarian Nordic shares.
J&J has simplified and fast-tracked its vaccine programme in the light of the world's worst Ebola outbreak, which is still ravaging Liberia, Sierra Leone and Guinea.
Originally it had been working to develop a vaccine against both the Zaire and Sudan strains of Ebola, as well as a related condition called Marburg disease. It is now developing a vaccine targeting only the Zaire strain behind the current epidemic.
Although the safety and effectiveness of such experimental vaccines has yet to be proven, they have provided good protection against the Zaire strain of Ebola when tested on macaque monkeys, which is seen as a promising sign that they are likely to work in humans.
Like a number of other experimental vaccines against various diseases that are now in development, J&J's vaccine uses a common cold virus, called an adenovirus, to carry its payload.